It would definitely be post-1968, since the PPk/S didn't exist before that (this is a PPK slide on a PP frame, assembled because the PPK didn't meet the post-68 import criteria), but I don't have any serial number records to give a definite year. There are a number of Walther collectors at http://forums.p38forum.com/forums/viewforum.php?f=10 that can probably give you a ballpark figure.
